000
WTNT42 KNHC 172050
TCDAT2
 
POST-TROPICAL CYCLONE RAFAEL DISCUSSION NUMBER  21
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL172012
500 PM AST WED OCT 17 2012
 
ALTHOUGH SOME WEAK CONVECTION HAS REDEVELOPED NEAR THE CENTER OF
RAFAEL THIS AFTERNOON...THE OVERALL STRUCTURE OF THE CYCLONE HAS
BECOME THAT OF AN INTENSE EXTRATROPICAL CYCLONE.  EARLIER ASCAT
DATA SHOWED A FRONTAL BOUNDARY IMPINGING ON THE NORTHWESTERN
PORTION OF THE SYSTEM...AND AS OF THIS AFTERNOON...THE FRONT IS
ANALYZED INTO THE CENTER OF THE CYCLONE.  THEREFORE...RAFAEL
HAS BECOME EXTRATROPICAL...AND THIS WILL BE THE FINAL NHC
ADVISORY ON THIS SYSTEM.  THE ASCAT DATA INDICATED A LARGE AREA
OF 50-60 KT WINDS OVER THE SOUTHEASTERN PORTION OF THE
CIRCULATION...SO THE INITIAL INTENSITY REMAINS 65 KT. SOME
GRADUAL WEAKENING IS FORECAST DURING THE NEXT COUPLE OF DAYS...
BUT THE LOW IS FORECAST TO REMAIN A LARGE AND POWERFUL SYSTEM OVER
THE NORTH ATLANTIC FOR THE NEXT SEVERAL DAYS.
 
RAFAEL HAS TURNED NORTHEASTWARD.  THE TRACK FORECAST REASONING
REMAINS UNCHANGED FROM THE PREVIOUS ADVISORY.  THE CYCLONE SHOULD
TURN EAST-NORTHEASTWARD DURING THE NEXT DAY OR SO...AND THEN
COMPLETE A CYCLONIC LOOP AROUND A DEEP-LAYER LOW OVER THE
NORTH-CENTRAL ATLANTIC IN 2 TO 3 DAYS. THE OFFICIAL FORECAST
IS SIMILAR TO THE PREVIOUS ADVISORY AND IS BASED ON A BLEND OF THE
GFS AND ECMWF MODELS.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  17/2100Z 40.2N  56.5W   65 KT  75 MPH...POST-TROP/EXTRATROP
 12H  18/0600Z 42.9N  50.9W   60 KT  70 MPH...POST-TROP/EXTRATROP
 24H  18/1800Z 46.0N  41.8W   60 KT  70 MPH...POST-TROP/EXTRATROP
 36H  19/0600Z 49.0N  33.0W   50 KT  60 MPH...POST-TROP/EXTRATROP
 48H  19/1800Z 52.0N  29.0W   50 KT  60 MPH...POST-TROP/EXTRATROP
 72H  20/1800Z 54.0N  33.0W   50 KT  60 MPH...POST-TROP/EXTRATROP
 96H  21/1800Z 47.6N  33.0W   45 KT  50 MPH...POST-TROP/EXTRATROP
120H  22/1800Z 43.0N  28.0W   35 KT  40 MPH...POST-TROP/EXTRATROP
 
$$
FORECASTER BROWN